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We propose an efficient liquid-phase hydrogenolysis system for the selective cleavage of an α-O-4 lignin model compound, benzyl phenyl ether (BPE), under mild conditions. By employing EtOH/H2O as co-solvent and a carbon black supported nickel (Ni/CB) catalyst in the presence of NaBH4 as the hydrogen source, BPE hydrogenolysis exhibited over 99% BPE conversion along with very high toluene (46%) and phenol (45%) yields. The catalytic performance of the Ni/CB catalyst was compared with those of various noble metal catalysts (Pd/C, Ru/C and Rh/C) for BPE hydrogenolysis. The results disclosed that the Ni/CB catalyst performs better than noble metal catalysts and exhibited higher selectivity for toluene and phenol under mild reaction conditions (80 °C). In the Ni/CB catalyst, the CB support assists in obtaining a higher yield of toluene and phenol and offers complete conversion of BPE compared to an activated carbon support (34% BPE conversion) in Ni/AC. The Ni/CB catalyst was synthesized by an impregnation method and fully characterized using various characterization techniques (XRD, SEM, TEM, XPS, ICP and FT-IR).

An effective and selective oxidation of 5-hydroxymethylfurfural (HMF) using hydrogen peroxide (H2O2) as the liquid oxygen source and activated carbon supported ruthenium (Ru/AC) as the catalyst was demonstrated in this work. This reaction system allows HMF to be oxidized in water and mild reaction conditions efficiently since it has relatively less mass-transfer resistance compared to gaseous oxygen-assisted oxidation systems. In addition, we could selectively control the components of oxidation products by adjusting the reaction conditions. We optimize several reaction parameters such as the reaction temperature (75 °C), times (t = 1 or 6 hr), additive base (sodium carbonate), and the ratios of HMF/catalyst (50 or 10) in order to attain the desired products with the maximum yield. The results showed that 5-formyl-2-furoic acid (FFCA) with a high yield up to 92% could be obtained at the conditions of HMF/catalyst = 50 and t = 1 hr while 2,5-furandicarboxylic acid (FDCA) with the maximum 91.3% yield could be obtained at the conditions of HMF/catalyst = 10 and t = 6 hr. A possible mechanism of such selective oxidation of HMF is also discussed. We envision that the H2O2-mediated oxidation systems proposed in this study would be a great benefit to other organic oxidation systems.

A new strategy to attach magnetic Fe3O4 nanoparticles (NPs) onto the commercially available immobilized lipase on acrylic resin is demonstrated. Magnetic Fe3O4 NPs-loaded lipase was successfully utilized as an effective and recyclable heterogeneous catalyst for producing biodiesel from soybean oil. In addition, the effects of different organic solvents on the yield of fatty acid methyl ester (FAME) and the stability of the Fe3O4-immobilized lipase were investigated. A maximum FAME yield of 44% can be achieved after the optimization of reaction conditions.